SiC crystal growth apparatus and method

Abstract

Disclosed is a SiC crystal growth apparatus including a reaction cell provided in a vacuum furnace such that SiC crystals are grown in the reaction cell, the reaction cell is configured such that a source is disposed in a lower region of an area defined by a crucible and a cover and a seed is provided below the cover, and a filter configured to filter out particles from gas supplied from the source is provided between the seed and the source, the filter includes a first layer, a second layer, and a third layer disposed in a direction from the source to the seed and spaced apart from each other, first through holes, second through holes, and third through holes are formed through the first layer, the second layer, and the third layer, respectively, and centers of the first to third holes form a face-centered cubic structure.

What is claimed is: 
     
       1. A SiC crystal growth apparatus, comprising:
 a reaction cell provided in a vacuum furnace such that SiC crystals are grown in the reaction cell, wherein the reaction cell is configured such that:
 a source comprising carbon and silicon is disposed in a lower region of an area defined by a crucible and a cover, and a seed is provided below the cover; and 
 a filter configured to filter out particles from gas supplied from the source is provided between the seed and the source, wherein:
 the filter comprises a first layer, a second layer, and a third layer overlapped in a direction from the source to the seed, and spaced apart from each other; 
 first through holes, second through holes, and third through holes are formed through the first layer, the second layer, and the third layer, respectively; and 
 the first through holes, the second through holes, and the third through holes are arranged not to overlap each other in a longitudinal direction. 
 
 
 
     
     
       2. The SiC crystal growth apparatus according to  claim 1 , wherein centers of the first through holes, the second through holes, and the third through holes form a face-centered cubic structure. 
     
     
       3. The SiC crystal growth apparatus according to  claim 1 , wherein the first layer, the second layer, and the third layer have a thickness of 1 nanometer to 10 centimeters. 
     
     
       4. The SiC crystal growth apparatus according to  claim 1 , wherein the first layer and the second layer or the second layer and the third layer are spaced apart from each other by 1 nanometer to 10 centimeters. 
     
     
       5. The SiC crystal growth apparatus according to  claim 1 , wherein the first through holes, the second through holes, and the third through holes have the same shape. 
     
     
       6. The SiC crystal growth apparatus according to  claim 1 , wherein the first through holes, the second through holes, and the third through holes have the same shape, but have different sizes. 
     
     
       7. The SiC crystal growth apparatus according to  claim 6 , wherein the size of the first through holes in a lateral direction is the largest, and the size of the third through holes in the lateral direction is the smallest. 
     
     
       8. The SiC crystal growth apparatus according to  claim 1 , wherein the first through holes, the second through holes, and the third through holes have a circular, polygonal, or oval cross-section. 
     
     
       9. The SiC crystal growth apparatus according to  claim 8 , wherein the cross-section of each of the first through holes, the second through holes, and the third through holes is decreased in the direction from the source to the seed. 
     
     
       10. The SiC crystal growth apparatus according to  claim 1 , further comprising an insulator configured to surround the reaction cell. 
     
     
       11. The SiC crystal growth apparatus according to  claim 1 , further comprising a filter support configured to support an edge of the filter on an inner wall of the reaction cell. 
     
     
       12. The SiC crystal growth apparatus according to  claim 11 , wherein the inner wall of the reaction cell has an inclined portion configured to be inclined inwards from an upper region of the source to the filter support. 
     
     
       13. The SiC crystal growth apparatus according to  claim 1 , further comprising a fixing member configured to fix the seed to the cover. 
     
     
       14. The SiC crystal growth apparatus according to  claim 1 , wherein a width of an inner wall of the reaction cell at a height between the source and the filter is smaller than a width of the inner wall of the reaction cell at a height equal to the source and a width of the inner wall of the reaction cell at a height equal to the filter. 
     
     
       15. A SiC crystal growth method, comprising:
 disposing a source comprising carbon and silicon in a lower region of a reaction cell, and disposing a seed in an upper region of the reaction cell; 
 evacuating the reaction cell, and filling the reaction cell with inert gas; 
 heating the reaction cell; 
 again evacuating the reaction cell, and moving gas comprising carbon and silicon atoms from the source towards the seed; and 
 filtering out carbon or silicon particles from in the gas through a filter, wherein, in filtering out the carbon or silicon particles:
 the filter comprises first, second, and third graphite plates overlapped in a direction from the source to the seed, provided with first, second, and third through holes respectively formed therethrough, and having a thickness of 1 nanometer to 10 centimeters is used; and 
 centers of the first through holes, the second through holes, and the third through holes form a face-centered cubic structure. 
 
 
     
     
       16. The SiC crystal growth method according to  claim 15 , wherein, in filling the reaction cell, the reaction cell is filled with the inert gas at a pressure exceeding 600 Torr. 
     
     
       17. The SiC crystal growth method according to  claim 15 , wherein, in heating the reaction cell, the reaction cell is heated to a temperature of 2,000 to 2,500° C. 
     
     
       18. The SiC crystal growth method according to  claim 15 , wherein, in again evacuating the reaction cell, the reaction cell is evacuated at a pressure of 0.1 to 100 Torr. 
     
     
       19. A SiC crystal growth apparatus, comprising:
 a reaction cell provided in a vacuum furnace such that SiC crystals are grown in the reaction cell, wherein the reaction cell is configured such that:
 a source comprising carbon and silicon is disposed in a lower region of an area defined by a crucible and a cover, and a seed is provided below the cover; and 
 a filter configured to filter out particles from gas supplied from the source is provided between the seed and the source, the filter comprising first, second, and third graphite plates overlapped in a direction from the source to the seed, wherein the filter has a plurality of passages configured to move the gas in a direction not parallel to a longitudinal direction. 
 
 
     
     
       20. The SiC crystal growth apparatus according to  claim 19 , wherein the plurality of passages comprises points configured to form a face-centered cubic structure in the filter.